Computer System Workload Manager

1. A computer-implemented method for enhancing a workload manager for a computer system having limited resources, said method comprising: sampling and storing usage of a resource of said computer system as time-stamped resource usage values; comparing said time-stamped resource usage values with predetermined time-stamped performance goal values; assigning, by said workload manager, a time-stamped priority value to an application that is running based on at least one of said performance goal values; retrieving a portion of said time-stamped resource usage values and a related portion of said time-stamped performance goal values for said application; identifying a future workload demand value by applying a time-series analysis algorithm to said time-stamped resource usage values and said time-stamped performance goal values for said application resulting in workload demand time frames and related amplitudes of said workload demand time frames; and adjusting a dispatch priority value for said application by setting a minimum dispatch priority for said application based on said future workload demand value.

2. The method according to claim 1 , wherein a time period for said portion of said time-stamped resource usage values is selected out of the group consisting of a millisecond, a second, a minute, an hour, a day, a week, a month, a year, two years, three years, four years, five years, and six years.

3. The method according to claim 1 , further comprising: applying weighting factors to said time-stamped resource usage values.

4. The method according to claim 1 , wherein said setting said minimum dispatch priority further comprises: determining periodically, based on said identified future workload demand, an exceeding of a workload threshold growth value; and performing said setting said minimum dispatch priority value only if said workload threshold growth value is exceeded.

5. The method according to claim 1 , wherein said adjusting said dispatch priority value also comprises: setting said minimum dispatch priority value such that said dispatch priority value will not be lowered below said minimum dispatch priority value for a fixed period of time.

6. The method according to claim 1 , wherein said application, said time-stamped resource usage values, and said predetermined performance goal value relate to a service class.

7. The method according to claim 1 , further comprising: defining an importance value (I app ) of said application.

8. The method according to claim 7 , wherein said adjusting said dispatch priority value also comprises: adjusting a target importance value (I target ) according to: if I app =1, then I target =1; and if I app >1, then I target =I app −1, wherein said importance value (I app ) is a current importance value of said application.

9. The method according to claim 8 , wherein said adjusting said dispatch priority value also comprises: adjusting a target dispatch priority value (DP target ) according to: if I target =1, then DP target =maxDP (I target )+1; and if I target >1, then DP target =avgDP (I target )+1, wherein maxDP is a maximum dispatch priority value assignable to said application; and wherein avgDP is an average dispatch priority assignable to said application.

10. The method according to claim 1 , wherein said resource is selected out of the group consisting of a central processing unit, an amount of main memory, an amount of cache memory, an amount of external storage capacity, a network capacity, and an input/output channel.

11. A workload manager system for a computer having limited resources, said system comprising: a sampling module adapted for sampling and storing a usage of a resource of said computer system as time-stamped resource usage values; a comparison unit adapted for comparing said time-stamped resource usage values with predetermined time-stamped performance goal values; an assignment unit adapted for assigning a time-stamped priority value to an application that is running based on at least one of said time-stamped performance goal values; a retrieving unit adapted for retrieving a portion of said time-stamped resource usage values and a related portion of said time-stamped performance goal values for said application; an identification module adapted for identifying a future workload demand value by applying a time-series analysis algorithm to said time-stamped resource usage values and said time-stamped performance goal values for said application resulting in workload demand time frames and related amplitudes of said workload demand time frames; and an adjustment unit adapted for adjusting a dispatch priority value for said application by setting a minimum dispatch priority value for said application based on said future workload demand value.

12. The system according to claim 11 , wherein a time period for said time-stamped resource usage values is selected out of the group consisting of a minute, an hour, a day, a week, a month, a year, two years, three years, four years, five years, and six years.

13. The system according to claim 11 , wherein the sampling unit is further adapted for applying weighting factors to said time-stamped resource usage values.

14. The system according to claim 11 , wherein said adjustment unit is also adapted for: determining periodically, based on said future workload demand value, an exceeding of a workload threshold growth value; and performing said setting of said minimum dispatch priority value only if said workload threshold growth value is exceeded by said future workload demand value.

15. The system according to claim 14 , wherein said adjustment unit is also adapted for setting said minimum dispatch priority value such that said dispatch priority value will not be lowered below said minimum dispatch priority value for a fixed period of time.

16. The system according to claim 11 , wherein said application, said resource usage values, and said predetermined performance goal value relate to a service class.

17. The system according to claim 11 , wherein the assignment unit is further adapted for defining an importance value (I app ) of said application.

18. The system according to claim 17 , wherein said adjustment unit is also adapted for: adjusting a target importance value (I target ) according to: if I app =1, then I target =1; and if T app >1, then I target =I app −1; wherein said importance value (I app ) is a current importance value of said application.

19. The system according to claim 18 , wherein said adjustment unit is also adapted for: adjusting a target dispatch priority (DP target ) according to: if I target =1, then DP target =maxDP (I target )+1; and if I target >1, then DP target =avgDP (I target )+1, wherein maxDP is a maximum dispatch priority assignable to said application; and wherein avgDP is an average dispatch priority assignable to said application.

20. A computer program product for enhancing a workload manager for a computer having limited resources, said computer program product comprising a computer readable storage medium having program instructions embodied therewith, said program instructions being executable by one or more computing systems or controllers to cause said one or more computing systems to: sample and store a usage of a resource of said computer system as time-stamped resource usage values; compare said time-stamped resource usage values with predetermined time-stamped performance goal values; assign, by said workload manager, a time-stamped priority value to an application that is running based on at least one of said time-stamped performance goal values; retrieve a portion of said time-stamped historic resource usage values and a related portion of time-stamped performance goal values for said application; identify a future workload demand value by applying a time-series analysis algorithm to said time-stamped resource usage values and said time-stamped performance goal values for said application resulting in workload demand time frames and related amplitudes of workload demand time frames; and adjusting a dispatch priority value for said application by setting a minimum dispatch priority value for said application based on said future workload demand value.